Controller for electric motors.



No. 884,002. PATENTED APR. 7, 1908. T. E. BARNUM &: H. H. CUTLER. OONTROLLER FOR ELECTRIC MOTORS.

APPLIOATION FILED JUNE18.1902.

0 L H B H ."m 4" 1 u. an ii I H m r m H H 3 /u No. 884,002. PATENTED APR. 7, 1908. T. 12:. BARNUM & H. H. CUTLER. CONTROLLER FOR ELE GTRIG MOTORS.

APPLIUATIOF TILED J UHE 18.1902.

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- 'PATENTED APR.,7, 1908.

T. E. BARNUM & H. H. CUTLER. CONTROLLER FOR BLEUTR'IG MOTORS.

APPLICATION FILED JUHE 18. 1902.

UNITED STA'lfES PATENT OFFICE.

THOMAS BARNUM AND HENRY-H. CUTLER, OF MILWAUKEE, WISCONSIN, ASSIGNORS To THE CUTLER-HAMMER MFGUO OF MILWAUKEE, WISCONSIN, A CORPORATION OF WIS GONSIN.

CONTROLLER FOR ELECTRIC MOTORS.

Specification of Letters Patent.

Patented April 7, 1908.

Appication filed June 18, 1902. Serial No. 112,203.

To all whom it may concern:

Be it known, that we, THOMAS E; BAR- NUM and HENRY H. CUTLER, citizens of the of this specification.

' crating electric elevators.

Our invention relates to controllers for electricmotors and preferably to such de vices used in connection with motors for op- It'has for its object-to provide in such a de v ce means to prevent admitting current to the motor except/when all or substantially all of thestarting'resistance is in circuit, and

also to prevent operating'the motor for any length of time with any of the resistance in the circifit of the motor, that is, the resistance-is usedfor starting only and notfor regulating;

The-invention further consists in the novel features hereinafter described and particularly pointed out in the ap ended claims.

In the accompanying rawings in which the same reference letters are used throughout the several views to designate like parts,

Figure 1 is a plan view of the controller box showing the several devices mounted there in Fi 2 isa side e evationof the same, the

, shaft eing. in section on the line 2 -2 of Fi arm 7 are ada 1; Fig; 3. is an elevation of the opposite si e of the box, and showing the rheostat devices;

and, Fig. 4 1s a diagram of the circuit connections. i

The controller box, 2 is of the form shown '1 .in Figs. 1, 2 and '3, andhas' mounted upon the face 3 which is preferably ofinsulation, a series of contact segments 4. with which the sec-1 tions 5 of the resistance of the rheo'stat are suitably connected, bymeans of binding osts in the usual manner; Suitable carbon rushes .6 :carried by the pivoted rheostat tedto engagethecontact segments 41in t e, movement of said" pivoted arm and'are yieldingly pressed against said segments by suitab e springs 8 .as shown.

The arm 7 is pivoted at" 9 and carries suitable brushes 10 to engage.thecontact plate 11 and connecting: the arm electringlly therewith.

The arm 7-is provided with an n tending portion or bracket 12' w wardly exch carrles brushes, preferably of t an insulated roller 13 shown more clearly in Fig. 1, at its u per point and upon its inner face, with which the heart shaped cam 14 engages, the said cam being rigidly mounted by means of a pin 15 upon the projecting end of the shaft 16 passing box. When the shaft 16 is rotated in either direction, the heart shaped cam 14 is likewise 'operated, and in this movement engages the roller 13 and lifts the arm7 to its normal POSI- tion as shown in Fig. 3. Upon the bracket 12 suitable brushes 17 engage stationary contacts for a purpose hereinafter explained, bearing segments 18 being provided for said brushes 17 when, the arm 7 is out of its normal position. The arm is maintained in its raised position by 'means of a dog or catch 19 adapted to engage beneath a lug 20 formed upon the arm 7 by means of a small plate see cured by SUlbEtlDlE screws thereto.

The armature ed to strike the catch or dog 19 in its upper movement when the magnet is energized thereby releasing the catch 19 to permit the arm to descend. This operation does not take place as hereinafter explained until the a heart shaped cam has been removed from beneath t e roller 13. A stop 23 limits the upward movement of the arm 7, while another stop 24 limits its downward movement. A suitable dash pot '25 is connected .1 ofthe magnet22 is adaptthroughthe controller with the arm 7 by means of the rod 26-and the bracket 12 towhich the rod is pivoted, the lower end of the dash pot cylinder being pivoted at 27. Suitable binding, posts or clips 28, 29 and 30, as wella's 31, 32, and 33 serve to connect the device in the electric circuit. I

The shaft 16 is extended through the box 2 and upon the op .osite end carries a revers ingswitch '34 wlnc is plrovided with suitable e carbon ty e at each and adapted to suitably engage wit the cor.-

tact'segments and rings mounted upon opposite fa'e of the box 2-, this face being li ewise of insulation. The reversing switch 34 carries brushes at a shorter end which electrically connect the inner ring'35. and the adj acent-segments 36, while at the opposite or longer end, similar'sbrushes connect the segments 36 with the ring 37, additional segments 38 and 39 are located outside of-the ring 37, while suitable restin 41 are also mounted uponjthe base. Suitable binding posts are also mounted upon the plates 40 and this face of the box to connect'the segments in suitable manner in the circuit. Upon the extended end of the shaft 16, that is, ,the end extending beyond the reversing switch 34 a suitable sprocket wheel 42 is mounted and with which the sprocket chain leading from the mechanism controlledbythe operating rope or lever from the elevator car engages.

The main controlling switch 43 of the ap paratus is mounted upon the end of the box as shown inFigs. l and 2, this switch is of the ordinary solenoid type and is therefore not shown or described in detail.

' Referring to Fig. 4 the operation is as follows: In the position shown in the'said figure, the parts are in normal position and the elevator car as well as the motor is at rest. 44 is a main switch in the power circuit which isassumed to be closed. Under normal conditions the reversing lever stands in the osition shown in full lines, and the heart s aped cam 14 is likewise in the posi tion shown in full lines. The brushes 6 of the arm 7 normally standupon the contact segment which is electrically connected with the starting or releasing magnet 22, the

latter being connected by a conductor 45 with the first'segment of the resistance 5 and is therefore in series in the startin with the arm 7 and resistance '5." T e series winding 46 of the motor is suitably connected at one end with a third contact from the end of the series, while its middle point is connected with the ends to the last contact and its opposite terminal is connected with the last contact of the series, the said term nal being likewiseconnected with one of the con tacts of the solenoid switch 43, the opposite "contact thereof being connected through a 40 conductor 47 with the negative side of the power circuit through the overload magnet 48, the overloadmagnet 48 being-adapted when actuated by an overload circuit to open the circuit through the winding of the switch 43. This switch is connected by means of a conductor 49 with the segments 38 of the reversing switch, suitable resistance lamps 50 being includedin said circuit when the arm 7 is out of its normal position, but be ng short-circuited by the brushes 17 of the said arm 7 when innormal position. Said brushes extend from opposite sides of the lamps 50110 the contacts upon which said brushes normally rest.

The shunt winding 51 of the motor is connected directly between the terminals of the 'switch 43 and the opposite side 52 of the power circuit.

The armature 53 of the motor is connected by conductors 54 and 55 with the two segments 36 of the reversing switch. I The arm 7 is connected by a cone 'ductor 56 with the ring contact 35 of thereversing switch and suitable resistance lamps 57 are copnected between the conductorjfi and the outer segment 39 of the reversing circuittors.

.motor in the reverse direction, the shaft 16 switch. The opposite conductor of the power circuit 52 is connected directly with the segment 37 of the reversing switch. Assuming that the main switch 44 is closed and that the shaft '1 6 with its cooperating parts are in normal position, it will be seen that in order to start the motor 53 it is necessary to first close the switch 43 which controls the admission of current to the motor armature and field windin s. In. order to operate this switch, the r aft 16 is rotated in one direction or the other according to the direction of movement which it is desired to impart to the motor 53, theposition shown in dotted lines being chosen for illustration. In this position, the point of the long arm of the switch 34 engages the contact segment 38 and completes a circuit from the negative side of the power circuit over conductor 47, through the overload magnet 48, winding of switch 43, conductor 49, around the shunt of lamps 50, to contaet'segment 38, the reversing switch 34, contactsegment 37., and conductor 52 to the opposite side of the power circuit. Owing to the shunting of theresistance lamps 50 the switch 43 is able to operate and closes the circuit through its contacts to the motor and-resistance, One of the paths of current which is now closed is through the shunt winding 51 of 'the motor and over conductor 58 to the opposite side of the power circuit. A second path is also completed through the series windipg 46 of the motor, the resistance 5, 'conductor'45, releasing magnet 22, arm 7,

of the-rheostat, conductor 56, contact ring 35, the brushes carried uponthe short-annof the switch arm 34, the left hand segment 36v of the reversing switch, conductor 55, armature 53', of the motor, conductor54, the right hand contact segment 36, thence through to the switch arm 34 to the contact segment 37 and out over the conductor 52 to the other side of the power circuit. This path completes a circuit through the armature of the motor whichpath includes the starting re} sistance 5 and the series Winding of the motor, the latter enabling the motorto start under load which is a condition most frequently met with in the operation of eleva'. llad it bcerrdesired tooperate the,

would have been rotated in the reversedirec 'tion which would have completed the same 'whole is removed from the circuit,,'the.last segments serving to out out first a portion of the series winding of the motor, and finally all of it. When the arm 7 moves down- Wardlyfrom its first position the circuit through the magnet 22 and the resistance 5 is opened so that neither the magnet nor the starting resistance 5 is injured by the continued flow of current. It will be observed be closed at contacts 38, 38, the heart shaped camis moved entirely out of the way of the roller-13, carried by the lever 7 so that the arm or lever is permitted to'descend as rapidly as the dash pot will permit. It is therefore impossible to keep any of theresistance 5 in the-circuit long enough to be injured by the-heavy current flowing; In etc ping the 1 motor the reversing switch is brouglit to normalppsition by rotating the shaft 16. In so doing, the arm 34 of the reversing switch passes ofl' fiom the contact segment 38 thus opening the circuit of the switch 43 which is deenergized and breaks the circuit leading to the motor 53,-whereby. the same is caused to stop. I l

When once the switch arm 34 passes off I from the segment 38 it engages the segment 39 and, completes the circuit from the arm 7, over conductor 56, through the lamps 57, contact'fs'e mer t 39, the switch arm 34 to the contactB path being" parallel toftha t passin the armature 53 ofthe motor. g of. this r r 0 ened ,t e;kick due to the self induction 0 the shuntwinding 51 of the motor is prothrough y reason videdwith'an outlet or path which takes up the surge'andiwhereby the s ark and other 40 injurious effects of the kick is prevented.

Owing to the inclusion of the lamps in the circuit of the s'witch 43, it is now impossible to again operate the said switch, even should the operator attempt to do so by moving the 4 5, reversing switch into the operating position.

In other words, it is necessary for the op- ;cratorto restore the arm .7 so as to short circuit lamps 50before the motor can. be again started. This operation however, again cuts in the resistance 5 so that an unduly large .current cannot be thrown upon the motor. It will-therefore be seen that when the switch 43 is opened for any reason Whatever, it is impossible to again operate it until the reversing switch and the arm 7 have been brought back to normal position and thereby cutting in the resistance 5 and pre venting all injury to the motor thereafter.

While a we have described the invention with particular reference to the specific method shown of carrying the same into practical effect, we do not wish to so confine our invention, for it is obviously capable ofmany changes without departing from the. scope or prinbiple thereof. For example, the.

that before the circuit of the switch 43 canand out to conductor 52; this ath'as soon as the switch 43 ismagnet 22 may be connected irrseries with the shunt field, or in other relation so as to be operated by the operation of switch 43'.

Having described our IIIVQIHIO'II what we claimas new and desire to secure by Letters Patent is: v

1. In a controller, the combination with an electric motor of a resistance therefor,'a

device for automatically removing said-7'.

sistance from the circuit of the motor, hand:

operated means for operating said device to insert the resistancein the motor circuit, and.

el ctrically controlled meansfor prevent' Y moving said resistancefrom the motor cir-' cuit, hand operated means for operating'said device to insert the resistance in themotor circuit, means to prevent the operation -.of said removing device until said hand operated means has been sufiiciently operated to permit all of said resistance to be removed from the motor circuit, and means for operating said switch to close the motor circuit.

3. In a controller, the combination with an electric motor, of a resistance therefor, a device for automatically removing said resistance from the motor circuit, hand operated means for operating said device to insert the resistance in the motor circuit, electrically controlled means to prevent the operation of said removing device until said hand operated means has been operated to permit all of the resistance to be removed from the motor circuit, a switch for controlling the circuit through the motor and through said electrically controlled means, and suitable means for operating said switch.

4. In a controller, the combination withan electric motor, of a resistance therefor, 'a

device for automatically removing said resistance from the motor circuit, hand operated means for operating said device to insert said resistance in the motor circuit, electrically controlled means to prevent the operation of said removing device until said hand operated means has been operated sufliciently to permit all of said resistance to be removed from the circuit, a switch for controlling the motor circuit and the circuit through said electrically controlled means,

and means to prevent the starting'of the motor except when all of the resistance is in circuit therewith. I I

5. In a controller, the combination with an. electric motor, of a resistance therefor, an.

automatically actuated movable element for removing said resistance from the motor circuit, hand operated means for operating mined time, electrically controlled-means for permitting operation of said device, an

electrical switch for starting sald motor, and

tion of the first mentioned switc operation of said movable element until said hand operated means for operating said .device to nsert the resistance in the motor said removing device for controlling the therefor, a device for "automatically remo v I sited means has been sufficiently operated. to

device for automatically removing said.

said movable element to insert said resistance in the motor c1rcn1t,and an electrically controlled demos for preventln the hand operated means has been sufliciently operated to permit all of the resistance to he removed from the motor circuit.

6. in a controller, the combination with an electric motor, of a starting resistance therefor, a device for automatically removing said resistance from the motor circuit, hand operated means for operatihg said device to insert the resistance in the motor circuit, means to prevent the operation of said removing device until said .hand operated means has been sulliciently operated to permit all of said resistance to be removed from the motor circuit, and means for controlling the speed otthe motor. l I 7. ln a controller, thecombination With an electric motor, of a startingresistance therefor, a device for automatically removing said resistance from the motor circuit,

circuit, means to; prevent the operation of said removing device until said hand operated means has been sufliciently operated to permit the removal of all ofsaid resistance from the rnotorcircuit, and means controlled by speed of the motor.

8.ln a controller, the combination with an electric motor, of a starting resistance ing saidresis'tance' fromthe motor'circui't,

hand operated means -for operating said device, to insert the resistance in the motor. circuit, means to prevent'the operation of said removmg dev1cc untll sald hand operermit all of'said resistance to be removed omthe motor circuit, and means controlled by said removing device for reducing the strengthcf the field of the motor and thereby controlling the speed thereof; I 9; In a controller, the combination with-an electric motor, of a resistance therefor, a

resistance from said motor in a predeter= actuating said electrically controlled means, and a second switch for controllingqthe opera- 10. In a controller, the combination with cient stre While permitting oWof suflicient current to 90 an electric motor, of a resistance therefor, a

Ba ance device for automatically removing said reslstance from said motor In a predetermined time, electrically controlled Ideans for permitting operation. of said device, an electrical i switch for starting saidmotor, and actuatin said electrically controlled mea'ns, a secon switch for controlling the operation of the to an electric motor, of a resistance therefor, an

automatically actuated movable el'ement for removing said resistance from the circuit of said motor in a predetermined time, a. ma net for permitting operationof said movab e element, an electrically controlled switch for starting said motor and energizing said magnet to set said movable element in operation, means for preventing the starting of the motor except when said resistance is in circuit, and means for returning said movable element to its initial position when the motor 1s stopped.

12. The combination of an electric motor,

a device for starting the latter, mechanism for varying the res stance of the motor clrcuit, electrically; controlled means for permitting operation. of said mechanism, means adapted to revent flow of current of sulfingt to o aerate said starting device,

retain said starting device in Whatever relationit may previously have occu ied, and a low resistance device for causing ow of cur rent, when said mechanism is in a highresistance condition, of amount sufficient to operate said starting device.

13. Inc controller, the combination with a motor, of an electrically operated switch for the circuit of said motor, 'a resistance for said motor, a device for.automatically'removmg said resistance from the circuit of said -motor' In a predetermlnedtime, means for permitting operation of said device vvhen the motoris started, means for operating sald switch to start the motor, and means to lob prevent the starting of the motor except when said resistance IS in circuit therewith.

In Witness whereof, We have hereunto subscribed our names in the'presence of tvvo Witnesses.

THOMAS E. BARNUM.

, HENRY H. CUTLER.

Witnesses: i

.' Ronr. V. Mommas, W. S. REED. 

